Lifting jack



I. V. K. HOTT LIFTING JACK Filed Ja n.2l, 1925 3 Sheets-Sheet 1INVENTOR.

[0/1 M K. H T

A TTORNEY Dec. 20, 1927. 1,653,179

I. v. K. HOTT LIFTING JACK Filed Jan.2l, l925 *Sheets-Sheet 2 INVENTOR.

fan KA. k07'7" A TTORNEY Dec. '20, 1927. 1,653,179

I. V. K. HOTT LIFTING JACK Filed Jan.2l, 1925 3 Sheets-Sheet 3 IN V ENTOR.

A TTORNEY rigidly secured to and preferably formed integral with theshaft. This collar is connected with the brake member by means of keys28 so that the brake member will be caused to rotate with the shaft andto move longitudinally therewith. The worm 20 is loosely mounted on theshaft 21 so that it may have rotatory and axial movement with relationthereto. hen the worm wheel 19 is rotated by the screw 5 upon thedownward movement of the load it will impart to the worm 20 an endthrust toward the brake member 24 and this thrust will force the brakemember into firm frictional contact with the cooperating frictionsurface 25 and thereby hold the worm wheel and screw against furthermovement. This holding device is constantly operative and will instantlycheck the reverse movement of the load between the successive operationsof the operating lever on the shaft 15. When the worm 19 is rotated in aforward direction by the; rotation of the shaft 15, by means of theoperating lever, the end thrust imparted to the worm 20 will move theworm in the opposite direction and will release the same for rotationwith the worm wheel. In the present instance, the worm is formedseparate from the brake member 24 and the ad jacent ends of the worm andbrake member are provided with cooperating clutch teeth 29. The endthrust imparted to the Worm by the forward movement of the worm wheel 19will disengage these clutch teeth to permit the worm to rotaterelatively to the shaft 21 and the brake member. To reduce to a minimumthe frictional resistance to the rotation of the worm I have interposedbetween the end thereof and the bearing 23 an anti-friction endthrustbearing 30 with which the end of the worm will contact when it is movedto the right. in Fig. 2,. by the forward movement of the worm wheel 19.It willbe apparent, therefore, that when the lifting mechanism isoperated to elevate the load. the worm 20 will rotate freely with theworm wheel 19 and will offerno appreciable resistance to the operationof the mechanism, but as soon as the operation of the lifting mechanismis interrupted the weight of the load will impart a reverse movement tothe worm wheel 19 which will cause the worm to be instantly connectedwith the brake mem ber 24; and this brake member firmly seated againstits cooperating brake member, thus instantly locking the worm againstrotation and thereby locking the load against down-. ward movement.

When it is desired to lower the load the brake member 2a is moved to aninoperative position but its connection with the worm 20 is maintainedso that this worm cannot be rotated with relation to the shaft 21 by thereverse movement of the worm wheel 19. This is accomplished by impartingaxial movement to the shaft 21 and to this end I member 24 into aninoperative position.

Movement is imparted to the sleeve 31 by means of a crank or handle 35which is mounted thereon and as here shown this handle is mounted on apin or shaft36 mounted iii-lugs 37 formed integral with the sleeve 31 sothat it may be moved into an inoperative position, as shown in Fig. 2,when not in use. In order to retain the handle in either its operativeor its inoperative position the hub portion 38 thereof is provided withtwo re *esses 39 spaced apart and adapted to receive a detent, In thepresent device, this detent is in the form of a plunger 4:0 slidahlymounted in lugs 37 pan allel with the. axis of the handle and having anenlarged portion 41 which may be moved into and out of the recesses 39.of the plunger opposite the enlarged portion all thereof extends througha hollow boss 42 forming a part of one of the lugs 37 and has mountedthereon a head 43 between which and the lug is coiled a spring 4% whichtends to move the enlarged end of the plunger into its operativeposition. The pressure of the thumb upon the head L3 will move theplunger against the tension of the spring 44; and disengage the detentportion thereof from the hub of the handle. The recesses 39 in the hubof the handle are so arranged that one of them will be in line with thedetent when the handle is in its operative position and the other willbe in line with the detent when the handle is in its inoperativeposition. To insure the release of the shaft and brake member from. thesleeve 31 the hub of the handle is provided with an inclined or camsurface 45 which is arranged. to engage the pin 83 when the handle ismoved to its inoperative position and to thus shift the pin to the innerend of the helical slot Yhcn the handle 35 is in its folded orinoperative position as shown in Fig. 2, it lies hack of 2: lug 46 onthe frame or hearing in which the shaft 21 is journaled and therebylocks the shaft against movement in a lowering direction and positivelyprevents the lowering of the load until the handle has been moved intoan operat ve position.

'lhe operation of the device will be readily understood from theforegoing description and it will be apparent that when the lift Thatend Hit) llll

lower "the 10- thtifrm "thereby tioh of sttid'cfahk tbifendefleztitimake mend tiptin the downward move-- vtfien t ojf the 1 Ld fa sh 3 ft, hbrake enhheeted shaft, nieehiijg with said .Voi'n'twmeel and I rtiigi'edthat the evil thiusrt imparted "1 hfdkebherh 'e', "a handle "for'rbtetinf; $22 It! shaft "a ntl stud mi-m; iii '11 direetio'n to lowerthei 10%.!!! "andf c pablqiist :1 limited '4. In a liftihg jtckg thecombination with a. lifting element, hhd meafis 'for actuating:

the Same to'eleva'te a load, 'oft'a, worm Wheel tiiih "thereby hpbji'the dowllwztrd m nven lent (if the 102th esheft, a b'rzike'cohnectedwith Said Shaft, h Wfntmfinqhnted 0n Said shaft,

jh'e'shing with 'said worm Wheel a'ncteo arfainged that the end thrustimparted thereto bye'ai Wbiin Wheel will 'ren'dei Said brake Opeiatiw'en'handle rotatable "about the axis of saidehaft, and means controlled bysaid g. ivorm in '3 direetibh to handle to tendersaid brake iiio perati've and said pin and said the same to elevate a load, of a wormwheel connected with said lifting element for rotation thereby upon thedownward. movement of the load, a shaft, a worm mounted on said shaftand meshing with said worm wheel, a brake member mounted on said shaftand arranged to be moved into an operative posi tion by the end thrustimparted to said worm by said worm wheel, and means supported by saidshaft for moving the same longitudinally to render said brake member inoperative. p

r 6. In a lifting jack, the combination with a lifting element, andmeans for actuating the same to elevate a load, of a worm wheelconnected with sei l lifting element for rotation thereby upon thedownward movement of the load, a shaft, a worm mounted on said shaft andmeshing with said worm wheel, a brake member mounted on said shaft andarrangedto be moved into an operative position by the end thrustimparted to said worm by said worm wheel, an operating handle mounted onsaid shaft, means connected with said handle to impart axial movement tosaid shaft upon the initial movement of said handle and to then rotatesaid shaft.

7. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to elevate a load, of a worm wheel connected withsaid lifting element for rotation thereby upon the downward movementofthe load, a shaft, worm mounted on said shaft and meshing with saidworm wheel, a brake member mounted on said shaft and arranged to bemoved into an operative position by the end thrust imparted to said wormby said worm wheel, a sleeve mounted on said shaft and having a helicalslot, a pin carried by said shaft and extending into said slot, and ahandle connected with said sleeve.

8. In a lifting jack, the combination with a lifting element, and meansthe same to elevate a load, of a worm wheel connected with said liftingelementfor rotation thereby upon the downward movement of the load, ashaft, a worm mounted on said shaft and meshing with said worm wheel, abrake member mounted on said shaft and arranged to be moved into anoperative position by the end thrust imparted to said worm by said worm.wheel, a sleeve mounted on said shaft and having a helical slot, a pincarried by said shaft and extending through said slot, and a handleconnected with said sleeve, said handle being pivotally mounted on saidsleeve and having means to cause sleeve to have relative movement whensaid handle is moved about the axis of its pivotal connection with saidsleeve.

9. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to "elevate a load, of a worm wheel connectedwith said lifting element for rotafor actuating tion thereby upon thedownward movement of the load, a shaft mounted for both rotatory andaxial movement, a brake member rigidly secured to said shaft, a wormmounted on said shaft for both rotatory and axial movement with relationthereto and meshing with said worm wheel, means controlled by the axialmovement ofrsaid worm to connect it with said shaft when said worm ismoved in one direction and to disconnect theworm from the shaft when theworm is moved in the other direction, and means for imparting axial.movement to said shaft to render said brake member inoperative.

10. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to elevate a load, of a worm wheel connected withsaid lifting element for rotation thereby upon the downward movement ofthe load, a shaft mounted for both rotatory and axialmovement, a brakemember rigidly secured to said shaft, a worm slidably and rotatablymounted on said shaft and meshing with said worm wheel, the adjacentends of said worm and said brake member having cooperating clutch faces,and means for imparting axial movement to said shaft.

11. In a lifting jack, the combination with a. lifting element, andmeans for actuating the same to elevate a load, of a worm wheelconnected with said lifting element for rotation thereby upon thedownward movement of the load, a shaft mounted for both rotatory andaxial movement, a brakemember rigidly secured to said shaft,- a wormslidably and rotatably mounted on said shaft and meshing with said wormwheel, the adjacent ends of said worm and said brake member havingcooperating clutch faces, a member rotatably mounted on said shaft, saidmember and said shaft having parts cooperating to impart axial movementto said shaft when said member is rotated in one direction, and meansfor actuating said member. 7

12. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to elevate a load, of a worm wheel connected withsaid lifting element for rotation thereby upon the downward movement ofthe load, a shaft mounted for both rotatory and axial movement. a brakemember rigidly secured to said shaft, a Worm slidably and rotatablymounted on said shaft and meshing with said worm wheel, the adjacentends of said worm and said brake member having cooperating clutch faces,a sleeve rotatably mounted on s'aidshaft, held against axial movement inone direction and having a helical slot, a pin mounted on said shaft andextending into said slot, and a handle connected with said sleeve.

13. In a lifting jack, the combination with lifting element, and meansfor actuating the same to elevate a load, of a worm Wheel connected withsaid tation thereby uponth'e downwa-rd move ment of the load, a shaftmounted for both rotatory and i axial movement, a brake member rigidlysecured to saidshaft a worm slida-bly and rotatabl mounted on saidshaftand ineshing With said worm wheel, the adjacent ends of said wormand said brake member havingcooperating clutch viaees, a

sleeve rotatablymounted on said shaftyheld against axial movements inone}.direetion and having a helical slot, a, 'pin mounted :on :saidshaft a nd extending flute said slot,

, a-hand-le pivota-llymounted on said sleeve on van axis transverse tothe axis of said shaft,

and neans for ;-retaining said handle in either of two positions withrelationto said Vs've. n

ll i-Inza-lil ting. ack, the combination with elevatealload, of a wormwheel connected with said lifting element for .frov tation thereby uponthe downward movement of the load, a shaft mounted "for {both rotatoryand axial movement, a fbrake member rigidly secured to said shaft, aworm slid-ably and,rotatably mounted on aid-shaft and meshing .withusaid worm wheel, the adjacent ends "of said brake I I clutch faces, asleeve rotatablymountedon said shaft, held against axial movement in onedirection and having a helicalslot, a, ,pin -inounted on said I throughsaid slot, a handlepivotally mounted on said sleeve, on an axisextending transversely to the a'xis of said -s1eeve,jsaid handle havinga part recesses, and a plun'ger yieldably; mounted eitherof saidrecesses.

, adapted to enter one of on said sleeve for, movement into andjefit of15., In a lifting aek the combination 7 "cans for actuating the same toelevate a load, of; a worm :wheel,

connected with said lifting eleinent fffor rotat-ion {thereby upon thedownward moveber rigidly secured tojsaid Shaft/it worm and meshing withsaid acentends of member having worm wheel, the adsaid worm and {sa dbrake cooperating fclutoh faces, a

sleeve rotatably 'mounted' on said shaft, held against axial movement inone direetiona-nd having a helical slot, a pin mounted on said shattandextending through said slot, at handie ,pi'votally mounted on saidsleeve on an axis extending transversely to the axis of said sleeve,said handle having ahub ,portion provided with slidably mounted on saidsleeve adjaeen't to said hub and having hub, a spring tending to ,movesaid enlifting element for ro brakes member having w an operating shaftsaid worm and, member having; cooperating said shaft, wheel and shaftand extending ;said worm withv said brake =proviqhed with l'oc'kmg saida1n,-a ment of the load, ashaft mounted for both rotatory and axilmovemen't, a brake niem- K V I V bevele slidably and rotatablymountedonsaid shaft separated recesses, a plunger,

an enlangec'l portion the recesses in said larged portion of, saidplunger into said flrecess, said plungerhaving means for moving the sameagainst the action of said spring to release said hub.

l6. Ina lifting jack-,the combination with ffltatory and 4' axialmovement, a brake member. FTIglCllY, secured to said shaft, a worm slidably and rotatably mounted on I said shaft and meshing with the,adjacent ends of said worm and :said 7 cooperating -clut ch taces asleeve rotatably mounted on said shaft, held-aga nst axial movement inone A 7 direction and having ahlicalslot, "a ,pin t ll ting element,andmea nsgfor (actuating thesarne to mounted on said shaft and extend ngthrough said slot, and a handle 'gpivotally mounted on said sleeve on anaxis transverse to the axisot' said sleeve andhaving a oam-shapedportion said pm when handle directionaboutits axis; n g In a liftinyljackja lifting element,

connectedwith said liftingeiement for rotation in either directiontzherebyga worm wheel rigidly secured to a worm meshing with said worm-ea tpable of a limited axial :moveanent, abrake ;member adapted 'to beconnected with or-disconnected from said worm,

means controlled the end thrust imparted i to said worm by worm wheel toconnect member andto ;-render said brake member operative, and means fori nparting axial movement to both said worm and said brake member torendersaid brake member inoperative. T ith v 7 18. in a lifting ,jack, abarse astandard rising -f-rom said base,,-a= ram sii dably mounted in.said standard, a nut carried by screw rotatably mounted on said baseandoperatively engaging said nut, a beveled E g-"ear rigidly fOOIlZlQCiQClwith said sorewya'beve-led pinion meshing with said 01 gear, agear-rigidly connected with saidgpini'on, a ,pinion meshing with thelast- ;inentioned gear, means ior actuating said pinion, a worm.wheelrigidly connected with said pinion, a worm meshing with-saidwormwheel, a brake member, means'controlled by the end thrustim-parted tosaid worm by Worm wheelto connect the same with and disconnect the sameifronrsaid brake member and to render said brake member operative, andmeans forgimparting, axial movement to said worm and saidibrakeinein herto render the brake 'member inoperative but retaining a connectionbetween the same and the worm r n 19'. In a lifting deck, a base, astandard rising from said base, a ram slidably wornrwheel,

arranged to engage is moved in one said shaft and mounted in saidstandard, a nut carried by said ram, a screw rotatably mounted on saidbase and operatively engaging said nut, a beveled gear rigidly connectedwith said screw, a beveled pinion meshing with said beveled gear, a gearrigidly connected with said pinion, a pinion meshing with the lastmentioned gear, means for actuating said pinion, a worm wheel rigidlyconnected with said pinion, a shaft extending transversely to the axisof said worm wheel and mounted for rotatory and axial movement, a brakemember rigidly connected with said shaft, a worm rotatably and slidablymounted on meshing with said worm Wheel, said worm and said brake memberhaving cooperating clutch faces, and an operating member connected withsaid shaft for imparting axial movement thereto to render said brakemember inoperative and for rotating the same to actuate said worm.

20. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to elevate a load, of a worm wheel connected withsaid lifting element for rotation thereby upon the downward movement ofthe load, a-worm meshing with said worm wheel and capable of axialmovement, a brake member actuated by the axial movement of said worm toprevent the rotation thereof, means for moving said brake member into aninoperative position and for rctating said worm in a direction to lowerthe load on said lifting element, and means for positively locking saidworm against rotation in a lowering direction.

21. In a lifting jack, the combination with a lifting element, and meansfor actuating the same to elevate the load, of a worm wheel connectedwith said lifting element for rotation thereby upon the downwardmovement of the load, a worm meshing with said worm wheel and capable ofaxial movement, a brake member actuated by the axial movement of saidworm to prevent the rotation thereof, a lowering crank, means controlledby the rotation of said crank to render said brake member inoperative,whereby said worm may be rotated and the load lowered. and meanscontrolled by said crank to positively lock said worm against rotationin a lowering direction.

22. In a lifting jack, the combination witha lifting element, and meansfor actuating the same to elevate a load, of a worm wheel connected withsaid lifting element for rotation thereby upon the downward movement ofthe load, a shaft, a brake con,- nected with said shaft, a worm mountedon said shaft, meshing with said worm wheel and so arranged that the endthrust imparted thereto by said worm wheel will render said brakeoperative, a handle connected with said shaft and capable of a limitedrotation about the axis thereof, means controlled by a lifting element,and

said handle to render said brake inoperative, said handle beingmovable'about an axis transverse to said shaft into an inoperativeposition, and means cooperating with saidhandle when the latter is in aninoperative position to hold said shaft positively against rotation in alowering direction.

23. In a lifting jack, the combination with means for actuating the sameto elevate a load, of a worm wheel connected with said lifting elementfor r0- tation thereby upon the downward movement of the load, a shaftmounted for both rotatorya nd axial movement, a brake member rigidlysecured to said shaft, a worm slidably and rotatably mounted on saidshaft and meshing with said worm wheel, the adjacentvends of said wormand said brake member having cooperating clutch-faces, a sleeverotatably mounted n said shaft, held against axial movement in onedirection and having a helical slot,a pin mounted on said shaft andextending into said slot, a handle pivotally mounted on said sleeve onan axis transverse to the axis of said shaft, means for retaining saidhandle in either of two positions with relation 'to said sleeve, and afixed stop to engage said handle when the latter is in one of saidpositions to hold said handle and sleeve against movement in a loweringdirection.

24:. In a lifting jack, the combination with a lifting'element, andmeans for actuating the same to elevate a load, of a deviceto controlthe downward movement of said lifting element comprising a brake, amovable member. to render said brake operative, means for connectingsaid movable member with'said lifting element to cause the former to bemoved in a direction to set the brake by the downward movement of saidlifting element, and manually operated means for moving said movablemember against the action of said lifting element to relieve thepressure on said brake and for actuating said movable member to permitof the downward movement of said lifting element. 25. In a lifting jack,the combination with a lifting element, and means for actuating the sameto elevate a load, of a device to control the downward movement of saidlifting element comprising a brake, a movable member to render saidbrake operative, means for connecting said movable member with saidlifting element to cause the former to be moved in a direction to setthe brake by the downward movement of said lifting element, and a singledevice for moving said movable member against the action of said liftingelement to release the pressure on said brake and for actuating saidmovable member to permit of the downward movement of said liftingelement.

26. In a lifting jack the combination with a lifting element, and meansfor actuating the same to elevate a load, of a device to control thedownward element comprising ber to render said i) for connecting saidmovement ofsaid lifting a brake, a movable membrake operat1ve,- means tto (illOll ement of saidlifting el movable member with cause theformerto to set the brake by ment, and a handle connected with said mo"-able member for moving the same against 10 the action ofsaid liftingelement to relieve the pressure on said brake. g

In testimony whereof, I afiix my signature hereto. I

. ION v, K. HOTT.

